Raster input/output scanner

ABSTRACT

A combined raster input and output scanner employing spaced document reading and copy printing arrays at a common read/write station. The document to be read and the copy to be printed are disposed in back to back relation and fed simultaneously to the read/write station between the document reading and copy printing arrays. The image reading array is a monolithic full line chip having dual staggered rows of image sensors with individual lenslets for focusing each sensor onto a scan line at the read/write station. To reduce cost, a minimum number of image sensors with relatively wide spacing therebetween is used. To offset loss of resolution, the reading array is movable between a first reading position where one-half of the document line is scanned and a second reading position where the remainder of the line is scanned. The copy printing array comprises a full line of ink jet nozzles, the number and disposition of the ink jet nozzles corresponding to the image sensors, the copy printing array being similarly movable between first and second copy printing positions concurrently with the reading array to thereby print the line in similar half-line increments.

This is a division, of application Ser. No. 442,555, filed Nov. 18,1982, now U.S. Pat. No. 4,496,984.

The invention relates to a combination raster input and raster outputscanner, and more particularly to an improved scanner incorporating amonolithic image read bar combined with a unitary print bar to permitsubstantially simultaneous reading and writing of a document originaland copy thereof.

Historically, copies of document originals have been produced by axerographic process wherein the document original to be copied is placedon a transparent platen, either by hand or automatically through the useof a document handler, and the document original illuminated by arelatively high intensity light. Image rays reflected from theilluminated document original are focused by a suitable optical systemonto a previously charged photoconductor, the image light raysfunctioning to discharge the photoconductor in accordance with the imagecontent of the original to produce a latent electrostatic image of theoriginal on the photoconductor. The latent electrostatic image soproduced is thereafter developed by a suitable developer materialcommonly referred to as toner, and the developed image transferred to asheet of copy paper brought forward by a suitable feeder. Thetransferred image is thereafter fixed as by fusing to provide apermanent copy while the photoconductor is cleaned of residual developerpreparatory to recharging.

More recently, interest has arisen in electronic imaging where incontrast to the aforedescribed xerographic system, the image of thedocument original is converted to electrical signals or pixels and thesesignals, which may be processed, transmitted over long distances, and/orstored, are used to produce one or more copies. Certain similarities,however, exist between electronic systems and xerographic systems, oneof which involves the need for an optical system to focus the image raysreflected from the document original onto the image reading array whichserves to convert the image rays to electrical signals. While discreteoptical image array systems are known to the art, it would beadvantageous in terms of economy and simplification if an integratedreading array/optical system chip could be provided.

Further, it would also be advantageous if the normally separate documentreading and copy printing operations could be combined. Presently,reading of the document original employs certain components such as adocument feeder, document scanner, etc., which are normally separatestructures from certain equivalent copy printing components. However,these copy printing components perform essentially the same function,that is, feeding a document which in this case is a sheet of copy paper,scanning which in this case comprises scanning a printing array, etc. Ifsome of these reading/writing functions could be combined, systemoperation and synchronization could be simplified and system costreduced through the use of fewer parts.

The invention relates to a monolithic full width image read bar forscanning documents comprising the combination of: an elongatedsubstrate; a plurality of photodetectors arranged to form at least onearray; a like plurality of lenses in optical relation with thephotodetectors, the number of lenses equalling the number ofphotodectors, and circuit means for processing image signals output bythe photodetectors.

The invention further relates to a reading/writing system including amonolithic image read bar having at least one array of reading elementsand optical means associated with each reading element for focusing thereading element onto the document line being read, the image read barreading a document image line by line at a read/write station; an imagewrite bar for writing copies of the document read by the read bar at theread/write station; the number in configuration of the writing elementsof the image write bar being identical to the number and configurationof the reading elements of the image read bar; means for operating theimage read and write bars in unison to substantially simultaneously readthe document and print copies thereof; and means for simultaneouslyfeeding in back to back relation the document to be read and the copysheet to the read/write station to permit reading of the document by theread bar while the print bar writes a copy of the document image on thecopy sheet.

IN THE DRAWINGS

FIG. 1 is a side view with cover removed of the combined raster inputand raster output scanner of the present invention;

FIG. 2 is an isometric view of the scanner shown in FIG. 1;

FIG. 3 is an isometric view showing details of the read and write barsof the present invention;

FIG. 4 is a logic schematic of the operating control for the scannershown in FIG. 1;

FIG. 5 is a timing chart illustrating the operational sequence of thescanner shown in FIG. 1; and

FIG. 6 is a diagram illustrating scan line coverage and overscan in atypical embodiment.

Referring to FIGS. 1 and 2 of the drawings, there is shown a combinedraster input scanner and raster output scanner, designated generally bythe numeral 10, of the present invention. For raster input scanning, animage read bar 12 scans or reads document originals 15 at read/writestation 29, the document image areas scanned being converted toelectrical image signals or pixels. While the image signals so producedmay be output to a suitable user such as a memory, communicationchannel, printer, and the like, in a preferred operational mode ofscanner 10 (R/W MODE), the image signals generated by read bar 12 areinput to the print bar 18 of ink jet type printer 17 which serves toproduce, i.e. write copies of the document original 15 in accordancewith the image signals on a suitable copy substrate such as copy sheetor paper 19, such copying being done substantially simultaneously withreading the document original 15.

As will be understood, the number of scanning elements or sensors thatcomprise image read bar 12 determine the initial scanning resolutionwhile the number of ink jet nozzles that comprise print bar 18determines resolution of the image copy. In a preferred arrangement, thenumber and arrangement of the sensors of image read bar 12 matches thenumber and location of the ink jet nozzles of print bar 18. A largenumber of sensors and ink jet nozzles may be provided to enhanceresolution. Alternately, to reduce cost and complexity, a relativelysmall number of sensors and ink jet nozzles (for example 88) may beemployed. Whatever the sensor and ink jet density, both image read bar12 and print bar 18 are oscillated harmonically in a direction (i.e. theX direction) substantially normal to the direction of document and copysheet movement to enhance resolution.

Scanner 10 includes a suitable frame or housing 22 within which imageread bar 12 and print bar 18 are disposed in opposed spaced relation ata read/write station 29. An input support or tray 32 for both documentoriginal 15 and copy sheet 19, which are scanned concurrently withdocument original 15 on top and copy sheet 19 on the bottom (thecombined document original and copy sheet are identified hereinafter bythe numeral 33), is operatively coupled to housing 22 at one endthereof, tray 32 preferably comprising an upwardly curved plate-likemember 35 fixedly attached to scanner housing 22 by suitable means (notshown). An upper guide 26 cooperates with tray 32 to form a slit-likeinlet 38 for receipt of the combined original/copy sheet 33. A suitablesheet detector 36 is provided at the inlet 38 to detect insertion of thecombined document/copy sheet 33. In the embodiment shown, the combineddocument/copy sheet 33 is inserted into inlet 38 by hand althoughautomatic feeding means may be contemplated for this purpose.

A feed roller 42 is provided downstream of inlet 38, the outer peripheryof roller 42 cooperating with end 26' of guide 26 to form a nip foradvancing the combined original/copy sheet 33 forward to read/writestation 29. Feed roller 42 is carried on a shaft 43 rotatably supportedin document housing 22. Shaft 43 is drivingly coupled by suitable means(not shown) to a suitable drive motor such as step motor 44. Aregistration stop 45 is provided on feed roller 42 to locate or registerthe combined document/copy sheet 33 on introduction thereof into inlet38. A retard slit 46 formed by spaced lower plate 47 and upper guide 48is provided in housing 22 downstream of feed roller 42 and upstream ofread/write station 29. Retard slit 46, through which the combineddocument/copy sheet 33 passes, serves in cooperation with the pinch rollpairs 40, 41 and 49, 50 to tension the combined document/copy sheet aswill appear.

Discharge pinch roll pairs 40, 41 and 49, 50 are disposed downstream ofread/write station 29, pinch rolls 40, 41 and 49, 50 being carried byshafts 51, 52, 53, 54 respectively. Shafts 51, 52, 53, 54, are rotatablysupported in housing 22 by suitable bearing means (not shown). As willbe understood, pinch roll pairs 40, 41 and 49, 50 cooperate to form nipsbetween which the combined original/copy sheet 33, following reading andwriting thereof at read/write station 29, is fed. To enable the combineddocument/copy sheet 33 to be tensioned, particularly for printingpurposes, pinch roll pairs 40, 41 and 49, 50 are coupled to step motor44 by suitable speed increasing coupling means (not shown) designed torotate pinch roll pairs 40, 41 and 49, 50 at a speed slightly in excessof the speed of feed rollers 42. Additionally, side edge supports (notshown) may be provided to further support the combined document/copysheet 33 as will be understood by those skilled in the art. A suitablesheet detector 37 is provided at read/write station 29 to detect arrivalof the combined document/copy sheet 33.

An output tray 56 is disposed on the downstream side of pinch roll pair49, 50 to receive the combined original/copy sheet 33 discharged bypinch roll pair 49, 50, the level of output tray 56 preferably beingbelow the nip formed by pinch roll pair 49, 50 to facilitate passage ofthe combined original/copy sheet 33 therein. Following depositing of thecombined document/copy sheet 33 in tray 56, document original 15 andcopy sheet 19 are separated as for example by hand.

To illuminate the document lines being scanned at read/write station 29,a suitable high intensity light source illustrated herein as elongatedlamp 59, is provided in housing 58 of read bar 12. Reflector 60 servesto concentrate the light rays emitted by lamp 59 onto the document atread/write station 29.

Referring particularly to FIG. 3, read bar 12 consists of a sandwichstructure formed from a sensor block 62, and intermediate aperture block64, and a lens block 66 joined together to form a unitary bar. Thelongitudinal dimension of bar 12 is preferably made sufficient to enableread bar 12 to effectively span the width of the document original to beread.

Sensor block 62 comprises a suitable substrate or base 68 such assilicon having parallel rows 69, 70 of photodiode elements or sensors 72which may be formed using thin film technology thereon. To enhance thepacking density of sensors 72 (and as it will be understood of the inkjet nozzles of print bar 18), the centerline of the sensors 72 of row 69may be offset from the centerline of the sensors of row 70 in the crossscan direction (the Y direction shown by the arrow). The image signalhandling and processing circuitry is preferably integrated onto base 68.As described, the number and disposition of sensors 72 on base 68 isdeterminative of image scan resolution, and in the embodiment shown arelatively few number of sensors 72 with relatively wide separationbetween the sensors themselves (i.e. along the scan or X direction) andthe sensor rows 69, 70 (along the Y direction) is provided. In oneexample, the diameter of sensors 72 may be 50 mils with separation ofapproximately 1.5 mils between adjoining sensors and an offset of 1.5mils between centerlines of the sensors 72 of row 69 relative to thesensors 72 of row 70.

Aperture block 64 which is formed of any suitable material impervious tolight such as epoxy, has rows 80, 81 of individual viewing apertures 82therethrough, the number of viewing apertures 82 and the dispositionthereof being the same as that of sensors 72. The dimension of viewingapertures 82 may be equal to the size of sensors 72 and preferablyslightly larger.

Lens block 66 comprises a unitary molded lens plate 85 of opticalquality polycarbonate or equivalent material formed to provide two rows87, 88 of lenses 90, the number and disposition of lenses 90 being equalto the number and disposition of sensors 72 and the cooperating viewingapertures 82. The diameter of lenses 90 is sufficient to permit lenses90 to collect light from the individual imaging areas viewed and focusthe image rays onto the sensor 72 associated therewith through theassociated viewing aperture 82, it being understood that the thicknessof aperture block 64 is chosen to provide an optical path of therequisite length.

Print bar 18 comprises plural rows 112, 114 of ink jet nozzles 115 towhich ink is supplied under pressure by pump 119 from a suitablemanifold reservoir 118. Preferably the number and disposition of ink jetnozzles 115 and ink jet rows 112, 114 is identical to that of sensors 72of read bar 12. Print bar 18 may be of the electrostatic type whereinthe individual streams of ink droplets emitted by nozzles 115 areselectively charged in accordance with image signals output by read bar12 by charge plates 120, 121, therebeing one pair of plates 120, 121 foreach ink jet nozzle. Where charged, the droplets are deflected from anormal course onto copy paper 19. Where not charged, the ink dropletsare collected by gutter 113 for return to reservoir 118.

Both image read bar 12 and print bar 18 are suitably supported such thatsensor row 69 and ink jet nozzle row 112 process one line while thesecond sensor row 70 and ink jet nozzle row 114 process a second line.Read bar 12 and print bar 18 have controlled harmonic movement in adirection substantially normal (i.e. the X direction) to the direction(i.e. the Y direction) of movement of the combined original/copy sheet33. For this purpose, read bar 12 and print bar 18 are jointly supportedby means of a mounting plate 100 (seen in FIG. 2) in predeterminedspaced relation to the plane of movement of the combined document/copysheet 33 through read/write station 29. Plate 100 is in turn supportedon base section 101 of frame 22, plate 100 together with read bar 12 andprint bar 18 being reciprocated back and forth through a preset distanceor stroke in the X direction.

To provide the aforementioned reciprocating movement of plate 100, aharmonic support comprised of flexure mounts 102, 103 are used tosupport plate 100 on base section 101. Each flexure mount 102, 103cormprises a substantially upright spring element 105 having a dependingcenter finger 106 secured to plate 100 flanked by depending side fingers108 fixedly attached to base section 101. Flexure mounts 102, 103 arepreferably relatively wide to minimize any sideways motion of plate 100and the read and print bars 12, 18 respectively supported therefrom.Since plate 100 can pivot about the top edge 100 of flexure mounts 102,103 while the top edge 110 can in turn pivot about the line 111 ofcontact between base section 101 and side fingers 108, a double pivotingaction is achieved which maintains read bar 12 and print bar 18 indesired spatial relationship with the combined document/copy sheet 33 atread/write station 29.

A suitable drive such as solenoid 107 is drivingly coupled to plate 100to move plate 100 and the read and write bars 12, 18 respectivelycarried thereby through a preset distance or stroke along the X axis.Suitable return means such as spring 109, which may be disposedinternally of solenoid 107, is provided to return plate 100 to theinitial read/write position following deenergization of solenoid 107.

Referring to FIG. 4 the control system for scanner 10 includes read baroperating circuit 125, print image processing circuit 126, ink jetoperating circuit 127, and overall system control circuit 130. Read baroperating circuit 125, which is preferably integrated onto read bar base68, includes a read control gate 132 for coupling each sensor 72 acrossvoltage source 134 and image signal output line 133. Control gates 132are energized in succession to provide a serial stream of image signalsto output line 133, a shift register 135 having successive output stagesthereof coupled by lines 136 to the control terminals of gates 132 beingprovided for this purpose. Clock pulses φ₂ for operating shift register135 are derived from system clock 140 through clock line 141.

Image signal processing circuit 126 comprises any suitable signalprocessing circuit or circuits and may for example include circuits foramplifying the signal output of sensors 72, DC restoration, thresholdingthe image signals, etc., as will be understood by those skilled in theart. Following processing, the image signals are fed through imagesignal output gate 190 to line 144 and ink jet operating circuit 127and/or to output line 191 and the remote user (not shown). Signalprocessing circuit 126 is driven in synchronism with read bar operatingcircuit 125 by clock pulses φ₂ input through clock line 146.

Ink jet operating circuit 127 includes a succession of print controlgates 149 for selectively coupling the individual electrostaticdeflector plate pairs 120, 121 associated with each ink jet nozzle 115with a suitable source of voltage 153. A distributing shift register 154has successive output stages coupled by gates 155 to the controlelectrode of gates 149. The control electrodes of gates 155 are coupledby clock line 156 to the φ₃ clock pulse output terminal of clock 140.The output of image processing circuit 126 is coupled by line 144through image signal input gate 193 to the loading terminal of shiftregister 154. As will appear, image signal input gate 193 permits inputof image signals to print bar 18 either from read bar 12 or other imagesignal source 195.

System control circuit 130 includes a suitable system controller 170 foroperating scanner 10 in either a read/write mode (R/W MODE) or read onlymode (R MODE) or write only mode (W MODE), controller 170 controllingenabling of step motor 44 through gate 172, and lamp 59, ink jet pump119, and clock 140 through lines 173, 175, 176 respectively. Controller170 initially controls through gate 180 enabling of solenoid 107, theoutput of controller 170 being coupled to gate 180 through line 178. Theother input of gate 180 is coupled through line 182 to a suitablesolenoid power source 183. The output of gate 180 is coupled by line 184to one input of solenoid control gate 185, the output of which iscoupled by line 187 to solenoid 107. The second input of gate 185 iscoupled by clock line 188 to the φ₄ clock pulse terminal of clock 140.

Clock 140 provides relatively high frequency and relatively lowerfrequency clock pulses φ₁ ' and φ₁, respectively to gate 172 foroperating step motor 44 at a relatively fast stepping rate designed toadvance the combined document/copy sheet 33 rapidly to read/writestation 29 and, during reading and writing, at a predetermined steppingrate in synchronism with the reading/writing process.

OPERATION

For operation of scanner 10 in the read/write mode, controller 170 isset to the R/W position to ready lamp 59, ink pump 119, clock 140,solenoid 107, and step motor 44 for operation. The operator or usermates the document 15 to be scanned with a copy sheet 19, with thedocument on top and the image to be copied facing upwardly. The combineddocument/copy sheet 33 is inserted into the nip formed by guide 26 andfeed roller 42, the leading edge of the combined document/copy sheetabutting against registration stop 45 of roller 42.

Insertion of the combined document/copy sheet 33 into inlet 38 isdetected by sensor 36 and controller 170 actuates clock 140 to outputrelatively high frequency clock pulses φ₁ ' to motor 44 to step thecombined document/copy sheet 33 forward through the slit 46 formed byplate 47 to read/write station 29 at a relatively fast rate. There, inresponse to a signal from sensor 37, controller 170 switches clock 140to the relatively lower frequency clock pulse rate φ₁ while actuatinglamp 59 and ink pump 119. Actuation of lamp 59 illuminates the documentarea being scanned while actuation of pump 119 supplies ink underpressure to ink jet nozzles 115 of print bar 18. The streams of inkemitted by nozzles 115, in the absence of any energizing voltage appliedto deflector plates 120, 121, are collected by gutters 113.

In the exemplary arrangement shown, a spacing of 10 lines is presumedbetween sensor rows 69, 70 and between ink jet rows 112, 114. Inasmuchas dual rows 69, 70 and 112, 114 of sensors 72 and ink jet nozzles 115are provided, step motor 44 is arranged to step the combineddocument/copy sheet 33 two lines at a time. Referring particularly toFIGS. 5 and 6 of the drawings, the clock pulse output φ₁ of clock 140momentarily energizes step motor 44 to turn feed roll 42 and pinch rollpairs 40, 41 and 49, 50 and step the combined document/copy sheet 33forward two lines to bring the second line (L2) of the combineddocument/copy sheet 33 opposite sensor row 70 and ink jet nozzle row114. In the example shown, it is understood that the combineddocument/copy sheet 33 has not reached sensor row 69 and ink jet nozzlerow 112 at this time.

On clock pulses φ₂, sensor read control gates 132 are actuated insuccession by enabling signals output by successive stages of shiftregister 135 to sample the arrays of sensors 72 of image read bar 12.The resulting serial image signal output passes through image processingcircuit 126, switch 190, line 144 and switch 193 to shift register 154of print circuit 127.

Image processing circuit 126 processes the image signal output of readbar 12 in a suitable manner to provide a stream of binary image signalswhich are loaded through successive stages of shift register 154.Following sampling of the last sensor 72 of read bar 12 and loading ofthe last image signal into shift register 154, clock pulse φ₃ from clock140 triggers gates 155 for a predetermined interval to couple the outputstages of shift register 154 to ink jet print control gates 149. Wherethe image signal in the shift register stage associated therewith isrelatively high (for example a binary 1), the print control gate 149 istriggered to couple voltage source 153 across the deflector plate pair120, 121 coupled thereto. The resulting electrostatic force deflects theink jet passing between so that the ink jet strikes the copy paper lineopposite thereto. Where the image signal in the shift register stage isrelatively low (for example a binary 0), the print control gate 149controlled thereby remains in an unactuated state and the deflectorplate pair associated therewith are not energized. Accordingly the jetof ink passing therebetween remains undeflected and is collected bygutter 113.

Following the predetermined printing interval, clock pulse φ₄ energizessolenoid 104 to displace read bar 12 and print bar 18 to the secondread/write position, movement of read bar 12 and print bar 18 beingsubstantially normal to the direction of feed of the combineddocument/copy sheet 33 along the X direction. As a result, sensors 72 inrow 70 and ink jet nozzles 115 in row 114 are disposed in position toread and write the in-between portions of the second line (i.e. lineL2). The aforedescribed read/write process is repeated to completereading and writing of the second line (line L2). Due to the spacing (inthis example, 10 lines) between the rows 69, 70 of sensors 72 and rows112, 114 of ink jet nozzles 115, the upstream sensor and ink jet rows69, 12 respectively are beyond the combined document/copy sheet 33 andhence do not scan or record any images.

Following completion of the read/print process, solenoid 104 isdeenergized to permit the combined read and print bars 12, 18, under theinfluence of spring 109, to return to the first read/write position andclock pulse φ₁ energizes step motor 44 to step the combineddocument/copy sheet 33 forward two lines. As a result, the fourth line(line L4) of the combined document/copy sheet 33 is disposed oppositesensor and ink jet nozzle rows 70, 114 respectively. The aforedescribedtwo stage read/write process is repeated to read and write the fourthline (line L4). Again, it is understood that sensor and ink jet nozzlerows 69, 112 respectively are beyond the combined document/copy sheet 33and therefore do not scan or record any images.

With completion of the read/write cycle, clock pulse φ₁ energizes stepmotor 44 to step the combined document/copy sheet 33 forward another twolines to bring the sixth line (i.e. line L6) opposite sensor and ink jetnozzle rows 70, 114 respectively, whereat the sixth line is read andwritten in the manner described. On the next step cycle, the eighth line(i.e. line L8) of the combined document/copy sheet 33 is processed. Thenext cycle of step motor 44 brings the first line (line L1) and tenthline (line L10) opposite sensor and ink jet nozzle rows 69, 112 and 70,114 respectively. On clock pulses φ₂ and φ₃, both lines L1 and L10 areprocessed, line L1 by sensor and ink jet nozzle rows 69 and 112respectively and line L10 by sensor and ink jet nozzle rows 70 and 114respectively. Following the predetermined printing interval, clock pulseφ₄ triggers solenoid 104 to displace read bar 12 and print bar 18 to thesecond read/write position to permit reading and writing of lines L1 andL10 to be completed in the manner described heretofore.

On the next read/write cycle, the combined document/copy sheet 33 isstepped another two lines to process lines L3 and L12, following whichthe next pair of lines are processed, and so forth and so on until theentire document/copy sheet 33 has been processed.

It will be understood that as the trailing edge of the combineddocument/copy sheet 33 reaches the reading/writing area, the sensor andink jet nozzle rows 70, 114 are no longer in operative position andhence cease to process the combined document/copy sheet 33. Sensor andink jet rows 69, 112 respectively, however, continue to process theremaining lines of the combined document/copy sheet until the trailingedge has passed thereby.

Where it is desired to operate scanner 10 in a document read mode only,controller 170 is set to the R position. In that setting, controller 170readies lamp 59, clock 140, solenoid 107, and step motor 44 foroperation. At the same time, the signal from controller 170 actuatesimage signal output gate 190 to route the image signal output ofprocessing circuit 126 to output line 191. The document 15 to be scannedis manually inserted into the inlet 38.

On a demand for image signals from the remote user which may for examplecomprise a memory, communication channel, printer, or the like, clock140 is actuated and the clock pulses φ₁ therefrom energize motor 44 tooperate feed roller 42 at a relatively high stepping rate to bring thedocument leading edge forward to read/write station 29. On detection ofthe document leading edge by sensor 37, controller 170 switches theclock output to pulses φ₁. As a result, step motor 44 drives feed roller42 and pinch roll pairs 40, 41 and 49, 50 at the relatively slowerstepping rate to step the document through read/write station 29 andpast read bar 12 two lines at a time. Read bar 12 operates in the mannerdescribed heretofore, sensors 72 of read bar 12, on clock pulse φ₂ beingsampled and the image signals produced, following processing by signalprocessing circuit 126, passing to output line 191 through gate 190.Following completion of the scan cycle, solenoid 107 is energized onclock signal φ₄ to displace read bar 12 to the second read/writeposition. On clock pulses φ₂, sensors 72 are again sampled to completereading of the remainder of the line or lines being read the the imagesignals passed to output line 191. Solenoid 107 is thereafterdeenergized to return read bar 12 to the first read/write position andon the next clock signal φ₁, the document is stepped forward another twolines and the process repeated. The foregoing is repeated until theentire document has been read.

Similarly, where printing only is desired, controller 170 is set to theW position, signals from controller 170 readies ink pump 119, clock 140,solenoid 107, and step motor 44 for operation. Image signal input gate193 is actuated, gate 193 coupled the load terminal of shift register154 to a suitable source of image signals exemplified herein as memory195. It is understood that the image signals in memory 195 have beenpreviously segregated into partial line segments, each partial linebeing comprised of alternate image signals. The copy sheet 19 to beprocessed is inserted into inlet 38.

As described, the copy sheet is advanced at a relatively rapid rate byfeed roller 42 to read/write station 29 following which step motor 44 isoperated at a relatively slow rate to step the copy sheet forward twolines at a time. At each step cycle, on clock pulses φ₂, the firstpartial lines of image signals in buffer 195 are clocked into shiftregister 154 of ink jet operating circuit 127. Following loading of theimage signals into shift register 154, the clock pulse φ₃ from clock 140actuates print gates 155 to deflect selective ones of the ink jetsemitted by nozzles 115 in accordance with the image signal content toprint the partial lines onto the copy sheet 19.

On clock pulse φ₄ solenoid 104 is energized to displace print bar 18 tothe second read/write position. Clock pulses φ₂ load the remainder ofthe line into shift register 154 and on clock signal φ₃, the print gates155 are selectively actuated to cause ink jet nozzles 115 to print theremainder of the two images lines. Solenoid 107 is then deenergized andon the next clock pulse φ₁, step motor 44 is actuated to step the copysheet 19 forward two lines and the above described process repeated. Theforegoing process continues until the entire copy image has beenprocessed.

It will be understood that in both the aforedescribed read only andwrite only modes, the document 15 or copy sheet 19 being processed ineach of these modes is initially read or written by one sensor or inkjet nozzle row 70, 114 respectively pending movement of the document orcopy sheet forward to a point where both sensor or ink jet nozzle rowsare in operative disposition with the document or copy sheet beingprocessed. Similarly, as the trailing edge of the document or copy sheetbeing processed passes from read/write station 29, processing is onlyeffected by sensor row 69 or ink jet nozzle row 114.

While the invention has been described in the context of an exemplary 10line space between adjoining sensor and ink jet nozzle rows 69, 70 and112, 114 respectively, other spatial relationships between the sensorand ink jet nozzle rows may instead be contemplated.

While the invention has been described with reference to the structuredisclosed, it is not confined to the details set forth, but is intendedto cover such modifications or changes as may come within the scope ofthe following claims.

I claim:
 1. A unitary part for images comprising in combination:(a) afirst section composed of a substrate having a plurality of imagesensors integral therewith which form at least one scanning array; (b) asecond section spaced from said first section, said second section beingcomposed of a substrate having a plurality of individual lenses integraltherewith for focusing image rays from the image being scanned onto saidsensors, there being one lens associated with each of said sensors; and(c) a third section intermediate said first and second sections forplacing said first and second sections in predetermined spaced operativejuxtaposition with one another, said third section being composed of asubstrate of light impervious material in face to face contact with saidfirst and second sections and having a plurality of apertures therein,there being one aperture associated with each of said sensors and lensesfor optically coupling each of said lenses with the sensor associatedtherewith in fixed prealigned relation with one another, the centerlinesof each of said image sensors being coaxial with the centerline of thelens and aperture associated therewith; said first, second, and thirdsections together forming a pre-aligned unitary part for scanningimages.
 2. The unitary part according to claim 1 in which said sensorsare arranged in two parallel scanning arrays, the centerlines of thesensors of one array being offset relative to the centerlines of thesensors of the other array, said lenses of said second section beingdisposed in two parallel arrays with the centerlines of the lenses ofone lens array being offset relative to the centerlines of the lenses ofthe other lens array in matching relation with the sensors of said firstsection;said apertures of said third section being disposed in twoparallel arrays with the centerlines of the apertures in one aperturearray being offset relative to the centerlines of the apertures of theother aperture array in matching relation with the centerlines of thesensors of said first section and the centerlines of the lenses of saidsecond section.
 3. The unitary part according to claim 1 in which saidfirst, second and third sections cooperate to form a generallyrectangular part for scanning images, the axis of said scanning arraybeing parallel to the longitudinal axes of said part.